DB2 - Problembeschreibung
Problem IC74787 | Status: Geschlossen |
Optimzer might yield a poor-performing access plan for queries that can make use of replicated MQTs. | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 | |
Problembeschreibung: | |
The problem occurs when the optimizer chooses a plan that repartitions the stream from the replicated MQT even when the source and target partition groups are same. This repartitioning is unnecessary, because the data is already available on all partitions. The fix will avoid such repartitioning. Example of unnecessary repartitioning is DTQ(26) below: ... | 100.9657 DTQ ( 26) 30.41432 2 | 760.7598 TBSCAN ( 27) 30.24803 2 | 760.7598 SORT ( 28) 30.23759 2 | 760.7598 >HSJOIN ( 29) 30.17059 2 /------+-------\ 760.7598 1 IXSCAN IXSCAN ( 30) ( 31) 10.60995 10.54317 1 1 | | 198982 18910 INDEX: HARI INDEX: HARI IND_REPL_MQT2 IND_REPL_MQT1 Q2 Q1 Partial details of TQ(26): Input Streams: ------------- ... Partition Map ID:3 ... Partition Column Names: ---------------------- +NONE Output Streams: -------------- ... Partition Map ID:3 ... Partition Column Names: ---------------------- +1: 'XYZ'+2: Q5.COLA | |
Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * All users. * **************************************************************** * PROBLEM DESCRIPTION: * * Without this APAR, customer is exposed to the issue as * * described in the "ERROR DESCRIPTION" section. * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 Version 9.5, Fixpack 8. * **************************************************************** | |
Local-Fix: | |
n/a | |
verfügbare FixPacks: | |
DB2 Version 9.5 Fix Pack 8 for Linux, UNIX, and Windows | |
Lösung | |
First fixed in DB2 Version 9.5, Fixpack 8. | |
Workaround | |
n/a | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 03.03.2011 06.07.2011 06.07.2011 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
9.5.FP8 | |
Problem behoben lt. FixList in der Version | |
9.5.0.8 |